Add an entry to the collection. Call this on the CPAN::PackageDetails object and it will take care of finding the right handler.

If you've set allow_packages_only_once to a true value (which is the default, too), add_entry will die if you try to add another entry with the same package name even if it has a different or greater version. You can set this to a false value and add as many entries as you like then use as_unqiue_sorted_list to get just the entries with the highest versions for each package.